Hoist structure



J. R. COFFING HOIST STRUCTURE Aug. 4, 1953 Filed Nov. 23, 1949 3 Sheets-Sheet l Ln QM J. R. COF F ING HOIST STRUCTURE Aug. 4, 1953 3 Sheets-Sheet 2' Filed NOV. 23, 1949 1953 J. R. COFFING 2,647,725

HOIST STRUCTURE Filed Nov. 23, 1949 3 Sheets-Sheet 3 PI.B

217 G'Av' l' 274- mmvroa. Jim's A. (arm/vs:

is not used. resides Patented Aug. 4, 1953 UN I TED STATES PATENT OFFICE 2,647,725 HOIST' STRUCTURE. James R. Coiling, Danville, 111. Application November 23, 1948, Serial No. 129,071 8 Claims, (01. 254-169) mal operation oration.

object of the invention is to provlde in certain embodiments thereof a swing vantage for hoist operation.

One feature of the invention, when-a. coil chain 1n the u ilization. oi? th newer sprocket. as a ratchet member and associating fully enclosed.

Other objects Will be set forth and .ieatures of the invention more fully hereinafter;

he. full nature of the. invention will be understQQd. from the accompanying drawings and the following description and claims:

In the drawings,

Fig. 1 is. a side elevation of a. coil or log chain hoist embodying the invention, the cradle thereof being shown in. the lowest position at the end of the maximum possible,- load elevating, stroke.

Fig. 2 is an end elevation, thereof with the handle omitted to show the parts with greater clarity;

Fig; 3- is a view similar to Fig. 1 and of the upper portion only oi said hoist, parts being conditioned for load lowering. I

Fig. 4 is a view similar to Fig. 1 and of a chain Fig. 6, is a sectional view through such a hoist and in the plane of the adapter axis with parts in elevation and parts removed.

Fig. 7 is the same view as Fig. 1 with parts a. that is; oscillatably supported within the ho sing upon a support shaft. i7 having; opposite ends hushed; as at. i3 and' [8' and su orted. in can boss; 20; on. side; till and sleeve 21. on. closure 22. seated in the enlarged aligned opening 23 in housing." I i and ecured as at: 22

The cradle opening; 213:, the latter being large. enough for su'clr purpose, andv secured in place within both homingand cradle; as. shown.

The cradle referred to: comprises a pair of spaced side walls 26 and 21 and has in side 21 a hole 28 large enough to pass the wheel and ratchet. The other side 26 has hole 29 to pass the shaft I1. The cradle thus is oscillatable upon shaft l1 and is oscillatable upon sleeve 2! of closure 22.

Each end 30 of the cradle terminates in a handle socket 3| that is adapted to detachably and interchangeably take an elongated handle member such as pipe 32. The detachable con nection can be of any desired or required type or may merely comprise a thread connection. v

Disposed inwardly and upon cradle wall 21 there is pivotally supported to ratchet engagement. Pivotally carried interiorly by wall H of the hoist housing and at 33 is load holding pawl 31 normally constrained to ratchet engagement by spring 38.

This spring at the end opposite that secured to the holding pawl is connected to a pin 39 carried as an offset portion by a positioning arm 49 in turn secured to rock shaft 4| that projects through the housing Wall H and externally mounts a manually operable control member 42. In Fig. 1 pawl 31 is disposed in the load elevating position. In Fig. 3 it is disposed in the load lowering position. The positioning arm at car.- ries a stop extension 43 positioned to be engaged by the heel of the load pawl 34 when raised to its extreme position for the beginning of a load elevating movement, as shown by dotted lines in Fig. 1. Such engagement assures positioning of the holding pawl in its locking and ratcheting engagement with the ratchet 24 or load wheel, and that arm 40 has moved spring 38 to its over center position to so position the pawl. The positioning arm 40 is limited in its swinging movement into and out position by the stops 40a and 4% carried by-the housing.

When the control member 42 is disposed as shown in Figs. 3 and 1, the holding pawl 31 is constrained to ratchet free position for load lowering. Upon load lowering it is cammed into ratchet tooth engagement by the upper curved camming surface of the load pawl 34 when it is elevated to its extreme uppermost position at the end of a load lowering stroke as shown in Fig. '7. Thus, when the holding pawl is in its free position shown in Figs. 3 and '1, engagement thereof by the load pawl 34 cams it into ratchet tooth engagement against the tension of spring 38 where it is held by its angle of draft of the tooth of ratchet 24 in contact with the tooth of the wheel, and in turn holds the load while the load pawl 34 is being returned to a new load receiving position in engagement with the ratchet wheel 24. As load pawl 34 moves into ratchet tooth engagement, the ratchet may be slightly moved to take the pressure off of the holding pawl 31, which will then snap free of its ratchet holding position under tension of the spring 38 to permit a load lowering step. The camming action between the load pawl and the holding pawl above described will swing the load pawl to a position to be latched by the latch 60 from ratchet tooth engagement during the return stroke for load lowering as hereinafter described.

The above briefly explains the relative pawl movements for load lowering. For load elevation the usual pawl and ratchet association is effected. For free chain operation, with no load upon the chain, the control is disposed for load lowering and pawl 34 is manually disengaged. This frees both pawls and the chain can be pulled freely at 33 an activating load pawl 34 normally constrained by spring 35v 4 through the hoist in either direction without pawl interference.

Reference will now be had to the lower portions of Figs. 1 and 2. Pivotally mounted upon the hub or craddle wall 21 at 54 is a catch and latch member 55 having cam face 56 and catch shoulder 51. Disposed adjacent thereto is cam pin 58 carried by pawl 34.

. The latch member is formed with an arm 59 to which the other end of spring 35 is secured. Said latch member also has a cam extension 60 formed with a cam face GI. Normally the spring 35 holds the cam face 56 of said member in inoperative engagement with the pin 58 carried by the pawl 34. Since the latch member is pivotally mounted at 54 on the cradle, the load pawl is thus biased into ratchet engagement about its pivotal mounting 33. Said latch and load pawl remain in this relation during load lifting operations. However, when the control member 42 of the holding pawl is moved to load lowering position as shown in Figs. 3 and '1, and load pawl 34 is swung to its extreme uppermost position into camming engagement with the holding pawl, it not only forces the holding pawl into ratchet engagement against tension of spring 38, but forcibly swings the load pawl relative to the latch member against tension of spring 35 until catch shoulder 51 looks over the cam pin 53. This has the effect of permitting the load pawl to be moved downwardly free of ratchet engagement with the holding pawl in holdin position as shown in Fig. '1. Upon downward stroke of the load pawl to a new ratchet engaging position for load lowering the cam face 51 of the latch member engages the stop bolt l4 swinging the catch shoulder out of engagement with the pin 58 to thus release the hold pawl into its new ratchet engagement, whereupon the above described lowering movement of the pawls will take place. This action may be described as a full load lowering step wherein two to three ratchet teeth may be passed over in moving the pawl back to a new load lowering position. When a short or so-called half stroke operation is desired, a pin 62 may be inserted in the threaded hole 62 of the hub or cradle as shown in Fig. '1. With this pin in place, the cam face 6! of the latch will engage therewith and release the pawl 34 following a shorter stroke, whereupon it will re-engage with the ratchet following only a one tooth free movement. Thus with the pin 62 out of place, stop bolt 14 by reason of its position will permit free movement of the pawl over a plurality of teeth before re-engaging which will enable the load to be lowered more rapidly than by a tooth to tooth lowering effected when the pin 62 is in position. Thus the operator has the choice of rapid lowering or a short tootih to tooth or step by step lowering of the This activation or operation is as follows:

For load elevation the control member 42 is positioned as shown in Fig. l. Pawls 31 and 34 ratchet upon ratchet 24 in handle oscillation within the limits for full or half stroke. The chain'advances accordingly. For load lowering the control 42 is positioned as shown in Figs. 3 and 7. When the handle nears the top of the stroke pawl 31 is engaged by pawl 34 and forced inwardly into ratchet engagement to take over the load theretofore carried by the load pawl 34. Continued handle elevational movement then causes the back face of pawl 31 to ride farther in on pawl 34 to tilt it upon pivot 33 sufficient for pin 58 on the load pawl to tilt trigger catch 55 so thatthe hook 57 engages or looks upon the pin.. This results, through spring 35, in freeing'the load pawl from the ratchet and disposing it so that, while the load is held by holding pawl 31, the handle 32 and load pawl 34 (now in retracted position) can be returned to the bottom of the stroke whether it be of full or half stroke type. In Fig. 1, full type, cam 6| engages stop M to tilt the trigger-catch til- 55 to release it from pin 58, whereupon spring causes load pawl 34 to engage the ratchet. Then the handle is slightly lowered to turn ratchet 24 a few degrees clockwise, see Fig. 1, which results in taking the load off pawl 37. pawl 31 immediately moves to inactive position, see Fig. 3. Then the handle carried load is lowered by elevating the handle until pawl 34 engages pawl 3'! as initially described. Free chain is effected in either direction by having no load on the chain, and with pawl 31 positioned as shown in Fig. 3 and pawl 34 latched in the inoperative position by the catch 51. Load pawl 34 must, by means of lowering handle 32, be positioned so as to allow pawl 3'! to clear ratchet 24.

Reference will now be had to Fig. 4 wherein a link chain or roller chain embodiment is illustrated. This form illustrates the omission of the ratchet, the pawls acting directly upon the chain rollers in lieu thereof. Herein also the half stroke type of operation is illustrated. The pawl-chain direct contact, if desired, can be employed in the log chain embodiment as well in which event the ratchet would be omitted. In all instances pawl draft is of importance to prevent pawl release accidentally.

'In Fig. 4 numerals .of the one hundred series indicate parts identical, similar or equivalent to parts shown in Figs. 1 to 3 and designated by the primary numerals. Herein I63 indicates the half stroke determiner stop disposed in hole 52. Herein also the shape of pawls 134 and I3"! are different in that each is toothed or notched at 134* and it! respectively. Also the load wheel lit now is in the form of a toothed sprocket wheel and the ratchet is omitted.

The several parts are assembled in a manner substantially comparable to that previously described. When a ratchet wheel is to be employed with the sprocket wheel the pawls may be identical to those (34 and 3?) shown in Figs. 1 and 2. Since Fig. 4 of the invention operates substantially the same as the first form, no further description of operation is believed necessary.

It will be obvious that in both forms of the invention described the handle is oscillated in a plane between the planes defined by the housing side plate portions. This of course requires the space between these plates to be open. In certain industries this is objectionable. This condition is especially accentuated when the cradle is of the interchangeable handle "accommodating type, the purpose of which was set forth 'initiallyherein, aswell as to dispose the handle oppositely when clearance demands it, as frequently happens when elevating a load in .a corner and when it 'is initially lifted it turns with the "hoist body and handle say "90 or so degrees'into the corner.

Whenever it is desired to substantially close the hoist housing except for openings for the chain to enter and leave, the handle is disposed at one side of such'housing. Howeverwith apredetermined fixed handle-cradle connection it wou'ldfrequent'ly occur that clearance would not Due to its constraint,

be available for full or half stroke purposes essential for hoist operation. Accordingly the handle when so disposed in an outboard relation, as it were, is adjustably associated with the hoist operating interior mechanism and it it swung to such position that the required handle travel can be attained.

The aforesaid embodiment of the invention is illustrated in Figs. 5 and 6 wherein numerals of the two hundred series designate parts identical, similar or equivalent to parts designated by the primary series of numerals in Figs. 1 to 3. Herein also the invention is shown as of the coil or log chain type but it will be obvious it can be of the chain link .or roller chain type. Furthermore it can include a ratchet or omit it, all as previously described hereinbefore.

In Figs. 5 and 6, 2 indicates one side of a hoist housing arranged to house chain wheel 225 carried by a shaft 2H. Herein both are integral. Side 210 is embossed at 2H! and includes bearing portion v122i! accommodating bus-hing 2H8 taking the adjacent end of said shaft. A yoke member having arm 210 is rotatably supported thereby. This at its opposite end 2' is enlarged as at 272 and is disposed exteriorly of housing pore tion 2 as shown.

Portion 212 is elongated outwardly and coaxially at 21.3 to form a sleeve in which is .disposed the other end of said shaft 211. The said free end is tapped at 274 to take bolt 275 for securing thereto a retainer .cap 216. Shaft 2 is hushed at 2 I Q in the inwardly directed collar portion '22! of housing portion 21 1.

Pivotally supported on a pin 233 carried by the arm 2?!) of the yoke member there is provided a load pawl 234 adapted to engage the ratchet teeth 22 secured about the shaft 2 l7. Associated with the load pawl there is provided a latch member 255 having a catch shoulder 25'! thereon. Said latch member is pivoted at 254 on the arm 210 or" the yoke member adjacent the load pawl 234. The load pawl and latch member are biased toward each other through the tension of the spring 235 secured to the latch member at one end and to the pawl at the other end. The pawl 234 carries a latch pin 258 adapted to be engaged by the catch shoulder 25 of the latch member for holding the pawl out of tooth engagement somewhat in the manner illustrated by the correspondingly enumerated elements of Fig. '7.

Pivoted on the housing adjacent the pawl and ratchet teeth there is a holding pawl 231 pivoted on the housing at 236 and positioned to swing into and out of holding engagement with said teeth. Adjacent the other end of the pawl there is provided a manually-operable control 242 pivoted at 24! upon the housing and yieldingly connected with the adjacent end of the holding pawl by the spring Zita-extending to the far end of an arm portion and-secured thereto at239. Thus movement of the control from one position to "anotherwi-ll throw the tension spring 238 over center for biasing said holding pawl into and out of position for tooth engagement. The holding pawl '23? is in such position and so related to the'load .pawl 23 i that upon moving the yoke member to extreme position to bring the load pawl :into 'camming engagement with 'theho'lding pawl, said load pawl will be cammed thereby free of toothed engagement and .into latched engagement, shoulder '25! (interlocking withpin .258 in "the manner illustrated .by the relative position of comparable elements as. shown in .Fig. .7.

7 Where desired the housing may be provided with a removable cover plate 222 secured at 222 to the housing portion 2H. The outwardly projecting end 213 of the yoke member 216, 211 provides a swing adaptor broadly comparable to the cradle of the embodiment of the inven tion as disclosed in Figs. 1, 2, 3 and 7, and includes a toothed periphery 211. The handle portion 230 includes a socket 23l to take an extension handle 232.

The handle portion is provided with a circular bore 218 the surface of which is rotatably supported by the crests of teeth 211 and includes boss 219 which slidably supports stem 280 of a latch member 281 normally constrained to interlocking engagement with the teeth 211 by spring 282. Member 283 is threaded to the handle and passes stem 280 and backs spring 282. It is slotted at 28d to take an aligning tooth 285. Stein 230 upon its outer end mounts knob 286 at 281. When the latch is in latching position the handle is locked to the yoke member in adjusted position. When the handle requires a different position due to lack of clearance it may be moved to such position with the latch disengaged, so that it can be oscillated through a half or full stroke without interference. When so adjusted, the latch is again engaged with the toothed end 273 of the yoke member.

It is to be noted that contrary to many hoist handles capable of 360 movement, the present invention provides for limiting the handle movement by the load holding pawl which functions as a stop. Hence, complete rotation of the handle is impossible in event the operators hand slips from the hoist handle. This constitutes a safety feature of the present invention.

While the invention has been illustrated and described in great detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character.

The several modifications described herein as well as others which will readily suggest themselves to persons skilled in this art, all are considered to be within the broad scope of the invention, reference being had to the appended claims.

The invention claimed is:

1. In a hoist structure for raising and lowering a load, a housing having bearings for supporting a shaft, a tooth load wheel on said shaft for operating a flexible load raising and lowering means, an oscillating hub rotatably mounted upon said housing concentrically with said shaft, a load pawl pivotally mounted on said hub normally biased into tooth engagement with said load wheel, a holding pawl pivoted on said housing, a control member rockable on said housing having a spring connection with said holding pawl movable to yieldingly constrain said pawl to load wheel holding position when moved in one direction and free thereof when moved in the opposite direction, a latch pivotally mounted on said hub adjacent said load pawl movable into latching engagement therewith upon said load pawl being oscillated to operative engagement with said holding pawl for latchjing said load pawl out of wheel operating position while forcing said holding pawl to its hold- ;ing position during a load lowering operation, and a camming element on said housing engageable by said latch upon said hub being oscillated a predetermined distance away from said holdwherein with the flexible ing pawl for camming said latch to release said load pawl to load wheel operating position.

2. A hoist structure as set forth in claim 1 wherein said camming element is selectively positioned for varying the distance of movement of the load pawl free of said load wheel during the load lowering operation.

3. A hoist structure as set forth in claim 1 load raising and lowering means free of load and the load pawl arrested in an intermediate position between its latched out and latch camming positions, said load wheel may be moved in either direction free of said pawls.

4. In a hoist structure as set forth in claim 1 wherein said oscillating hub comprises a cradle having a handle receiving socket extending from opposite sides thereof to provide for selective positioning of an operating handle on either side of said structure.

5. In a hoist structure as set forth in claim 1 wherein said hub is provided with an extension at one side thereof having a series of peripherally disposed teeth, a handle portion rotatably mounted about said toothed hub extension, and a latch member mounted in said handle portion normally constrained to tooth engagement with said hub portion for interlocking the handle portion therewith and movable free thereof for selectively positioning said handle portion relative to said hub portion.

6. In a hoist structure for raising and lowering a load, a housing having bearings for supporting a shaft, a toothed load wheel on said shaft for operating a flexible load raising and lowering means, an oscillating hub rotatably mounted upon said housing concentrically with said shaft, a load pawl member pivotally mounted on said hub movable into and out of tooth engagement with said load wheel, a holding pawl pivoted on said housing positioned for opposed engagement with the teeth of said wheel, a control member rockable on said housing having spring based connection with said holding pawl, a manually operable handle connected with said control member for rocking it to opposite positions for yieldingly throwing said holding pawl into and out of holding engagement with said load wheel, and a stop extension carried by one of said members positioned for operative engagement by the other said member for positively forcing said holding pawl into tooth engagement upon the beginning of a load lifting stroke.

7. In a hoist structure for raising and lowering a load, a housing having bearings for supporting a shaft, a toothed load wheel secured to said shaft for operating a flexible load raising and lowering means, an oscillating hub rotatably mounted upon said housing concentrically with said shaft, a load pawl pivotally mounted on said hub movable into and out of tooth engagement with said load wheel, a holding pawl pivoted on said housing positioned for opposed engagement with the teeth of said wheel, a latch associated with said load pawl movable into latching engagement therewith for holding it free of load wheel engagement during movement thereof from the end of a load lowering stroke to the beginning of the next load lowering stroke, and a member on said housing engageable by said latch for effecting its release of said pawl upon reaching a predetermined position relative to said wheel.

8. In a hoist structure for raising and lowering a load, a housing having bearings for supporting a shaft, a toothed load wheel on said shaft for 9 operating a flexible load raising and lowering means, an oscillating hub rotatably mounted upon said housing concentrically with said shaft, a load pawl pivotally mounted on said hub movable into and out of tooth engagement with said load wheel, a holding pawl pivoted on said housing positioned for opposed, engagement with the teeth of said wheel, a control member rockable on said housing having a spring connection with said holding pawl, a manually operable handle connected with said control member for rocking it to opposite positions for yieldingly throwing said holding pawl into and out of holding engagement with said load wheel, and a latch associated with said load pawl movable into latching engagement therewith for holding it free of load wheel engagement during movement thereof from the end of a load lowering stroke torthe beginning 10 of the next load lowering stroke, said latch being actuated to release said pawl into load wheel engagement upon said pawl reaching a predetermined position relative to said wheel, and means for rendering said latch inoperable relative to said load pawl during the load raising operation.

. JAMES R. COFFING.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 48,414 Lancaster June 2'7, 1865 325,614 Lancaster Sept. 1, 1885 2,051,832 Edelblute Aug. 25, 1936 2,243,361 Stahl May 27, 1941 2,377,324 Coiling June 5, 1945 Anglemyer Mar. 21, 1950 

